Olfaction has not been explored in virtual reality environments to the same extent as the visual and auditory senses. Much less research has been done with olfactory devices, and very few of them can be easily integrated into virtual reality applications. The inclusion of odor into virtual reality simulations using a chemical device involves challenges such as possible diffusion into undesired areas, slow dissipation, the definition of various parameters (e.g., concentration, frequency, and duration), and an appropriate software solution for controlling the diffusion of the odor. This paper aims to present a non-intrusive, mobile, low cost and wearable olfactory display, and a software service that allows the developer to easily create applications that include olfactory stimuli integrated with virtual reality headset glasses. We also present a case study conducted with 32 people to evaluate their satisfaction when using the olfactory display. Our findings indicate that our solution works as expected, producing odor properly and being easy to integrate to applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s00530-022-00908-8.

Software testing involves probing into the behavior of software systems to uncover faults. Most testing activities are complex and costly, so a practical strategy that has been adopted to circumvent these issues is to automate software testing. There has been a growing interest in applying machine learning (ML) to automate various software engineering activities, including testing-related ones. In this paper, we set out to review the state-of-the art of how ML has been explored to automate and streamline software testing and provide an overview of the research at the intersection of these two fields by conducting a systematic mapping study. We selected 48 primary studies. These selected studies were then categorized according to study type, testing activity, and ML algorithm employed to automate the testing activity. The results highlight the most widely used ML algorithms and identify several avenues for future research. We found that ML algorithms have been used mainly for test-case generation, refinement, and evaluation. Also, ML has been used to evaluate test oracle construction and to predict the cost of testing-related activities. The results of this paper outline the ML algorithms that are most commonly used to automate software-testing activities, helping researchers to understand the current state of research concerning ML applied to software testing. We also found that there is a need for better empirical studies examining how ML algorithms have been used to automate software-testing activities.

Anatomy learning is very important for many courses, and it requires understanding three-dimensional (3D) shapes, most forms of anatomy teaching are offered to students through two-dimensional (2D) resources, such as images and videos. Many software solutions were developed with the purpose of assisting anatomy teaching and learning, arranging varied techniques and assets, as interaction and visualization of 3D virtual models. Despite great features, these solutions lack standards utilization and pedagogical methodology. This paper aims to present a 3D content generation technique to Moodle, one of the most popular platforms for teaching and learning management, built upon a specific pedagogical methodology, and validated by educational experts. The standard used in this technique allow sharing and reuse of content not only among Moodle systems, which are used by a large number of educational institutions and professors but also in other Virtual Learning Environments.

A process-scheduling algorithm is a fundamental operating system function that manages the assignment of CPU (Central Processing Unit) processes. It aims to make the system efficient, fast, and fair, allowing as many processes as possible to make the best use of the CPU at any given time. Understanding scheduling algorithms and their impact in practice is a challenging and time-consuming task for students, given the differing features of each operating system. Operating system simulators are usually based on either a command line or bidimensional front-end interface. This paper presents a process-scheduling simulator based on virtual reality technology that allows students to develop their empirical skills while learning process-scheduling algorithms. The simulator allows the learner to navigate inside a computer motherboard and interact with its components in multi-projection environments such as CAVE-like systems (Cave Automatic Virtual Environment), on a desktop, in a Web browser, or using an HMD (head-mounted display) such as Google Cardboard.

Software libraries allow developers to create software projects upon basic functions already implemented. In this way, it is possible to focus on more complex activities to achieve the software solution aims. Software libraries features and availability on the Internet are the reason for these valuable project resources are widely used. However, there may be some issues in software projects that integrate several libraries, since they are independent projects that must work together. This paper presents LibViews, an information visualization application to create visual representations over libraries metrics and usage on software projects. LibViews was developed to provide a better understanding of libraries versions and their role in software projects, helping in the maintenance of these projects identifying previously unknown information. As use case, LibViews was applied in an university corporate software project, pointing out as a useful tool to understand the relationship between software project and its third-party libraries.

Improving the way that totally or partially deaf people communicate with the world is a challenging task for our society. One way to improve their communication is to learn sign language, which is a visual language based on hand shapes, orientations, and movements of the hands, arms, or body, and facial expressions. This paper aims to present a 3D virtual reality environment to allow deaf users to communicate with each other in a real-time, synchronous, instantaneous fashion via an online chat room and to assist the teaching-learning process of Brazilian Sign Language (LIBRAS). A three-dimensional avatar was developed which can translate words or sentences from Portuguese to LIBRAS. It was performed two experiments to evaluate the communication via the chat room: (1) with chat history enabled (visible) and (2) with chat history disabled (invisible). These evaluations involved 30 end-users, which confirmed that the virtual environment as developed here is effective to distance classes.